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Homemade face masks in public: What the CDC says about face coverings, N95 masks

The CDC has reversed its recommendations about using face masks as the coronavirus pandemic develops. Here's what that means.

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N95 face masks are currently in short supply.

South China Morning Post/Getty Images
For the most up-to-date news and information about the coronavirus pandemic, visit the WHO website.

In a response to the growing number of coronavirus cases in the US and new data on the transmission of the COVID-19 disease, the Centers for Disease Control and Prevention issued new guidelines this week on wearing face coverings in public, including cloth face coverings crafted at home. But what does that actually mean for you? 

The most important takeaway from the CDC's message is that covering your face when you leave the house is a "voluntary public health measure" and must not replace the most proven precautions, like self-quarantine at home, social distancing and thoroughly washing your hands.

The CDC is the US authority on protocols and protections against COVID-19, the disease caused by the coronavirus.

In the CDC's words, it "recommends wearing cloth face coverings in public settings where other social distancing measures are difficult to maintain (e.g., grocery stores and pharmacies) especially in areas of significant community-based transmission." (The emphasis is the CDC's.)

The institute says not to seek out medical or surgical-grade masks for yourself and to leave N95 respirator masks to health care workers, opting instead for basic cloth or fabric coverings that can be washed and reused. Previously, the agency considered homemade face masks a last resort in hospitals and medical facilities. 

For weeks, the debate escalated over whether homemade face masks should be used in hospital settings and also by individuals in public. It comes at a time when the available stock of certified N95 respirator masks -- the essential protective equipment used by health care workers fighting the coronavirus pandemic -- has reached critical lows. 

Read more: How to make a face mask or covering at home

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If you do have a supply of N95 masks on hand, consider donating them to a health care facility or hospital near you. Here's how to donate hand sanitizer and protective equipment to hospitals in need -- and why you should also refrain from making your own hand sanitizer.

In a medical setting, handmade masks aren't scientifically proven to be as effective at protecting you from the coronavirus. Why not? The answer comes down to the way N95 masks are made, certified and worn. It may not matter if care centers are forced to take a "better than nothing" approach.

Here's everything you need to know about the difference between homemade face masks and N95 respirator masks.

N95 masks vs. other masks: Facial fit and certification

N95 respirator masks differ from other types of surgical masks and face masks because they create a tight seal between the respirator and your face, which helps filter at least 95% of airborne particulates. They might include an exhalation valve to make it easier to breathe while wearing them. Coronaviruses can linger in the air for up to 30 minutes and be transmitted from person to person through vapor (breath), talking, coughing, sneezing, saliva and transfer over commonly touched objects.

Each model of N95 mask from each manufacturer is certified by the National Institute for Occupational Safety and HealthN95 surgical respirator masks go through a secondary clearance by the Food and Drug Administration for use in surgery -- they better protect practitioners from exposure to substances such as patients' blood.

In US health care settings, N95 masks must also go through a mandatory fit test using a protocol set by OSHA, the Occupational Safety and Health Administration, before use. This video from manufacturer 3M shows some of the key differences between standard surgical masks and N95 masks. Homemade masks are unregulated, though some hospital websites point to preferred patterns that they suggest using.

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One example of a hand-sewn face mask pattern.

ButtonCounter.com

Handmade face masks: Cotton and elastic

The DIY homemade face mask movement that's providing patterns and instructions for sewing face masks at home tell you to use materials like multiple layers of cotton, elastic bands and ordinary thread. 

By and large, the patterns contain simple folds with elastic straps to fit over your ears. Some are more contoured to resemble the shape of N95 masks. Still others contain pockets where you can add "filter media" that you can buy elsewhere. 

It's the belief of people who make their own masks that adding filters will help protect against transmission, particularly when it comes to larger particles from coughs and sneezes. 

Be aware that there isn't strong scientific evidence that the masks will conform to the face tightly enough to form a strong seal, or that the filter material inside will work effectively. Standard surgical masks, for example, are known to leave gaps. That's why the CDC emphasizes other precautions, like washing your hands and distancing yourself from others.

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What homemade masks were meant for first (not COVID-19)

Many sites sharing patterns and instructions for homemade masks were created as a fashionable way to keep the wearer from breathing in large particles, like car exhaust, air pollution and pollen during allergy season. They were not conceived of as a way to protect you from acquiring COVID-19. However, the CDC believes they might help slow the spread of coronavirus since other types of masks are no longer widely available.

One site, CraftPassion, includes this disclaimer:

Due to recent coronavirus attacks across the world, I have been receiving a lot of requests on how to add nonwoven filter inside the face mask. Disclaimer: this face mask is not meant to replace the surgical face mask, it is a contingency plan for those who have no avail to surgical mask in the market. Proper use of a surgical mask is still the best way to prevent virus infection.

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A video by manufacturer 3M demonstrates key differences between N95 and standard surgical masks.

3M/Screenshot by Jessica Dolcourt/CNET

CDC's original stance on homemade masks

Along with the World Health Organization, the CDC is the authoritative body that sets guidelines for the medical community to follow. The CDC's position on homemade masks has changed throughout the coronavirus outbreak.

On March 24, acknowledging a shortage of N95 masks, one page on the CDC website suggested five alternatives if a health care provider, or HCP, doesn't have access to an N95 mask. 

Here's what one CDC site had to say about homemade masks then:

In settings where face masks are not available, HCP might use homemade masks (e.g., bandana, scarf) for care of patients with COVID-19 as a last resort [our emphasis]. However, homemade masks are not considered PPE, since their capability to protect HCP is unknown. Caution should be exercised when considering this option. Homemade masks should ideally be used in combination with a face shield that covers the entire front (that extends to the chin or below) and sides of the face.

A different page on the CDC site appeared to make an exception, however, for conditions where no N95 masks are available, including homemade masks. (NIOSH stands for the National Institute for Occupational Safety and Health.)

HCP use of non-NIOSH approved masks or homemade masks

In settings where N95 respirators are so limited that routinely practiced standards of care for wearing N95 respirators and equivalent or higher level of protection respirators are no longer possible, and surgical masks are not available, as a last resort, it may be necessary for HCP to use masks that have never been evaluated or approved by NIOSH or homemade masks. It may be considered to use these masks for care of patients with COVID-19, tuberculosis, measles and varicella. However, caution should be exercised when considering this option.

Now, the CDC advocates for all civilians to wear a face covering when they leave the house.

Masks and sterilization

Another difference between homemade masks and factory-made masks from brands like 3M, Kimberly-Clark and Prestige Ameritech have to do with sterilization, which is crucial in hospital settings. With handmade face masks, there's no guarantee the mask is sterile or free from an environment with coronavirus -- however, measures like washing the masks might help combat that.

CDC guidelines have long considered N95 masks contaminated after each single use and recommend discarding them. However, the severe shortage of N95 masks has caused many hospitals to take extreme measures in an attempt to protect doctors and nurses, like attempting to decontaminate masks between use. One medical center in Nebraska, for example, is experimenting with ultraviolet light treatments to sterilize N95 masks.

In a potentially game-changing move, the FDA used its emergency powers on March 29 to approve the use of a new mask sterilization technique from an Ohio-based nonprofit called Battelle. The nonprofit has begun sending its machines, which are capable to sterilizing up to 80,000 N95 masks a day, to New York, Boston, Seattle and Washington, DC. The machines use "vapor phase hydrogen peroxide" to sanitize masks, allowing them to be reused up to 20 times.

Cloth or fabric face masks for home use can be sterilized by washing them in the washing machine.

The danger: Not knowing the limits

It's worth emphasizing again that sewing your own face mask may not prevent you from acquiring coronavirus in a high-risk situation, like lingering in crowded places or continuing to meet up with friends or family who don't already live with you. 

Since the coronavirus can be transmitted from someone who appears to be symptom-free but actually harbors the virus, it's crucial to the health and wellness of people over 65 and those with underlying conditions to know which proven measures will help keep everyone safe -- quarantine, social distancing and hand-washing being the most crucial, according to experts.

For more information, here are eight common coronavirus health myths, how to sanitize your house and car, and answers to all your questions about coronavirus and COVID-19.